Fehler in JS Datei

#1
Hallo Zusammen

Ich habe keine Ahnung von JS. Habe jedoch im JS Datei die herum bockt. Wegen dieser Datei wird mir ein Dropdown-Menu nicht angezeigt.

Firefox meldet folgenden Fehler:
TypeError: el is undefined
opening select2.js:formatted:2355
open select2.js:formatted:1892
initContainer/< select2.js:formatted:2507
bind/< select2.js:formatted:1354
dispatch jquery-1.7.2.min.js:3:4764
i jquery-1.7.2.min.js:3:692

Javascript:
SingleSelect2 = clazz(AbstractSelect2, {

        // single

        createContainer: function () {
            var container = $(document.createElement("div")).attr({
                "class": "select2-container"
            }).html([
                "<a href='javascript:void(0)' class='select2-choice' tabindex='-1'>",
                "   <span class='select2-chosen'>&nbsp;</span><abbr class='select2-search-choice-close'></abbr>",
                "   <span class='select2-arrow' role='presentation'><i class='fa fa-angle-down'></i></span>",
                "</a>",
                "<label for='' class='select2-offscreen'></label>",
                "<input class='select2-focusser select2-offscreen' type='text' aria-haspopup='true' role='button' />",
                "<div class='select2-drop select2-display-none'>",
                "   <div class='select2-search'>",
                "       <label for='' class='select2-offscreen'></label>",
                "       <input type='text' autocomplete='off' autocorrect='off' autocapitalize='off' spellcheck='false' class='select2-input' role='combobox' aria-expanded='true'",
                "       aria-autocomplete='list' />",
                "   </div>",
                "   <ul class='select2-results' role='listbox'>",
                "   </ul>",
                "</div>"].join(""));
            return container;
        },

        // single
        enableInterface: function() {
            if (this.parent.enableInterface.apply(this, arguments)) {
                this.focusser.prop("disabled", !this.isInterfaceEnabled());
            }
        },

        // single
        opening: function () {
            var el, range, len;

            if (this.opts.minimumResultsForSearch >= 0) {
                this.showSearch(true);
            }

            this.parent.opening.apply(this, arguments);

            if (this.showSearchInput !== false) {
                // IE appends focusser.val() at the end of field :/ so we manually insert it at the beginning using a range
                // all other browsers handle this just fine

                this.search.val(this.focusser.val());
            }
            this.search.focus();
            // move the cursor to the end after focussing, otherwise it will be at the beginning and
            // new text will appear *before* focusser.val()
            el = this.search.get(1);
            if (el.createTextRange) {
                range = el.createTextRange();
                range.collapse(false);
                range.select();
            } else if (el.setSelectionRange) {
                len = this.search.val().length;
                el.setSelectionRange(len, len);
            }

            // initializes search's value with nextSearchTerm (if defined by user)
            // ignore nextSearchTerm if the dropdown is opened by the user pressing a letter
            if(this.search.val() === "") {
                if(this.nextSearchTerm != undefined){
                    this.search.val(this.nextSearchTerm);
                    this.search.select();
                }
            }

            this.focusser.prop("disabled", true).val("");
            this.updateResults(true);
            this.opts.element.trigger($.Event("select2-open"));
        },

        // single
        close: function () {
            if (!this.opened()) return;
            this.parent.close.apply(this, arguments);

            this.focusser.prop("disabled", false);

            if (this.opts.shouldFocusInput(this)) {
                this.focusser.focus();
            }
        },

        // single
        focus: function () {
            if (this.opened()) {
                this.close();
            } else {
                this.focusser.prop("disabled", false);
                if (this.opts.shouldFocusInput(this)) {
                    this.focusser.focus();
                }
            }
        },

        // single
        isFocused: function () {
            return this.container.hasClass("select2-container-active");
        },

        // single
        cancel: function () {
            this.parent.cancel.apply(this, arguments);
            this.focusser.prop("disabled", false);

            if (this.opts.shouldFocusInput(this)) {
                this.focusser.focus();
            }
        },

        // single
        destroy: function() {
            $("label[for='" + this.focusser.attr('id') + "']")
                .attr('for', this.opts.element.attr("id"));
            this.parent.destroy.apply(this, arguments);
        },

        // single
        initContainer: function () {

            var selection,
                container = this.container,
                dropdown = this.dropdown,
                idSuffix = nextUid(),
                elementLabel;

            if (this.opts.minimumResultsForSearch < 0) {
                this.showSearch(false);
            } else {
                this.showSearch(true);
            }

            this.selection = selection = container.find(".select2-choice");

            this.focusser = container.find(".select2-focusser");

            // add aria associations
            selection.find(".select2-chosen").attr("id", "select2-chosen-"+idSuffix);
            this.focusser.attr("aria-labelledby", "select2-chosen-"+idSuffix);
            this.results.attr("id", "select2-results-"+idSuffix);
            this.search.attr("aria-owns", "select2-results-"+idSuffix);

            // rewrite labels from original element to focusser
            this.focusser.attr("id", "s2id_autogen"+idSuffix);

            elementLabel = $("label[for='" + this.opts.element.attr("id") + "']");

            this.focusser.prev()
                .text(elementLabel.text())
                .attr('for', this.focusser.attr('id'));

            // Ensure the original element retains an accessible name
            var originalTitle = this.opts.element.attr("title");
            this.opts.element.attr("title", (originalTitle || elementLabel.text()));

            this.focusser.attr("tabindex", this.elementTabIndex);

            // write label for search field using the label from the focusser element
            this.search.attr("id", this.focusser.attr('id') + '_search');

            this.search.prev()
                .text($("label[for='" + this.focusser.attr('id') + "']").text())
                .attr('for', this.search.attr('id'));

            this.search.on("keydown", this.bind(function (e) {
                if (!this.isInterfaceEnabled()) return;

                if (e.which === KEY.PAGE_UP || e.which === KEY.PAGE_DOWN) {
                    // prevent the page from scrolling
                    killEvent(e);
                    return;
                }

                switch (e.which) {
                    case KEY.UP:
                    case KEY.DOWN:
                        this.moveHighlight((e.which === KEY.UP) ? -1 : 1);
                        killEvent(e);
                        return;
                    case KEY.ENTER:
                        this.selectHighlighted();
                        killEvent(e);
                        return;
                    case KEY.TAB:
                        this.selectHighlighted({noFocus: true});
                        return;
                    case KEY.ESC:
                        this.cancel(e);
                        killEvent(e);
                        return;
                }
            }));

            this.search.on("blur", this.bind(function(e) {
                // a workaround for chrome to keep the search field focussed when the scroll bar is used to scroll the dropdown.
                // without this the search field loses focus which is annoying
                if (document.activeElement === this.body().get(0)) {
                    window.setTimeout(this.bind(function() {
                        if (this.opened()) {
                            this.search.focus();
                        }
                    }), 0);
                }
            }));

            this.focusser.on("keydown", this.bind(function (e) {
                if (!this.isInterfaceEnabled()) return;

                if (e.which === KEY.TAB || KEY.isControl(e) || KEY.isFunctionKey(e) || e.which === KEY.ESC) {
                    return;
                }

                if (this.opts.openOnEnter === false && e.which === KEY.ENTER) {
                    killEvent(e);
                    return;
                }

                if (e.which == KEY.DOWN || e.which == KEY.UP
                    || (e.which == KEY.ENTER && this.opts.openOnEnter)) {

                    if (e.altKey || e.ctrlKey || e.shiftKey || e.metaKey) return;

                    this.open();
                    killEvent(e);
                    return;
                }

                if (e.which == KEY.DELETE || e.which == KEY.BACKSPACE) {
                    if (this.opts.allowClear) {
                        this.clear();
                    }
                    killEvent(e);
                    return;
                }
            }));


            installKeyUpChangeEvent(this.focusser);
            this.focusser.on("keyup-change input", this.bind(function(e) {
                if (this.opts.minimumResultsForSearch >= 0) {
                    e.stopPropagation();
                    if (this.opened()) return;
                    this.open();
                }
            }));

            selection.on("mousedown touchstart", "abbr", this.bind(function (e) {
                if (!this.isInterfaceEnabled()) return;
                this.clear();
                killEventImmediately(e);
                this.close();
                this.selection.focus();
            }));

            selection.on("mousedown touchstart", this.bind(function (e) {
                // Prevent IE from generating a click event on the body
                reinsertElement(selection);

                if (!this.container.hasClass("select2-container-active")) {
                    this.opts.element.trigger($.Event("select2-focus"));
                }

                if (this.opened()) {
                    this.close();
                } else if (this.isInterfaceEnabled()) {
                    this.open();
                }

                killEvent(e);
            }));

            dropdown.on("mousedown touchstart", this.bind(function() { this.search.focus(); }));

            selection.on("focus", this.bind(function(e) {
                killEvent(e);
            }));

            this.focusser.on("focus", this.bind(function(){
                if (!this.container.hasClass("select2-container-active")) {
                    this.opts.element.trigger($.Event("select2-focus"));
                }
                this.container.addClass("select2-container-active");
            })).on("blur", this.bind(function() {
                if (!this.opened()) {
                    this.container.removeClass("select2-container-active");
                    this.opts.element.trigger($.Event("select2-blur"));
                }
            }));
            this.search.on("focus", this.bind(function(){
                if (!this.container.hasClass("select2-container-active")) {
                    this.opts.element.trigger($.Event("select2-focus"));
                }
                this.container.addClass("select2-container-active");
            }));

            this.initContainerWidth();
            this.opts.element.addClass("select2-offscreen");
            this.setPlaceholder();

        },

        // single


[/javascript]



Leider verstehe ich Null, was er mir da sagen will: